Developing Devices with 3-D Printing and FEA Software

A medical device developer details the use of 3-D printing and Finite Element Analysis software for the medtech industry.

Toby Cowe

The medical device industry is a landscape of ever-changing regulations, disruptive technologies and emerging markets. There have been notable trends in the last 12 months, including the discussion around connected devices and digital health, 3-D printing, and user-centered design.

3-D printing can be used to make protoypes rapidly.

Gartner’s 2015 Hype Cycle Special Report states that 3-D printing technology has progressed rapidly in recent years and that medical applications are at the forefront of some of the most significant deployments in 3-D printing technology. 3-D printers are increasingly used in the medical device industry at the development and prototyping phase. However, its use is heavily restricted by the materials available for use with them. According to Deloitte, the medical vertical is about 15 per cent of today’s 3-D printer market.

Evidence would suggest that there is going to be further growth in the development of 3-D printed medical products, a key driver behind this being the use of 3-D printing in manufacturing processes.

By utilizing 3-D printing technology at the rapid prototyping stage of development, there is an opportunity to completely transform the prototyping process with additive manufacturing. Until recently, in our work we would use a soft tool manufacturer to obtain the prototype components in the right materials to assess the reliability of a design. This would have taken a considerable amount of time and incurred a high cost. If the prototypes were to be used in human trials, the materials would need to be medically-approved.

The challenge with direct 3-D printing (this involves using inkjet technology which dispenses thick waxes and polymer resins which solidify to form incremental sections of the 3-D object) is that, although it is suitable for low volume items such as dental or possibly surgical applications, it is not suitable to produce high volume products such as disposable medical consumables.

With this in mind, we decided to use 3-D printing to create tools which can be used with any material, alongside an injection molding machine. This revolutionized our prototyping process. Through combining 3-D printing with the use of an injection molding machine, prototypes can be produced overnight.

One benefit of this is that there can be significant input at all stages of the design process from a number of different teams. Human factors insights are critical in this area and a user-centered design is extremely important in order to successfully meet the needs of the end-user. For example, in terms of dexterity, the needs of a patient with rheumatoid arthritis are different for those with multiple sclerosis and the design of the device needs to reflect this. Vital feedback is obtained through a combination of user groups and clinical experts. Through the use of 3-D printing, this feedback is received at an earlier stage in development. By producing three iterations in three days rather than three months, this creates the opportunity to prototype quickly. Therefore, the entire design and prototyping process becomes even more dynamic and ultimately benefits the end-user.

Another topic that has been key over the past year is the use of Finite Element Analysis (FEA). FEA is software used to analyse the structural integrity of parts, a process which can be carried out during all design stages of product development. Through using this kind of technology, this creates the ability to predict how a product will react to real-world physical effects such as vibration or heat. Furthermore, the design functionality can be interrogated at the geometric extremes produced by variations in the manufacturing process. This helps to reduce risk associated with different environments and test that a product’s integrity will remain the same, for example, if faced with extreme heat or force.

FEA is a computerized method of testing—a mathematical approach to risk. By understanding the design aspects of how a product would work in practice through specific calculations, at an early stage in design, the device can be tailored to the end-user at the primary stage of development.

Disruptive technologies, emerging markets, and an ever-evolving landscape of regulations and requirements will continue to impact the medical device industry throughout 2016. It’s clear that 3-D printing looks set to stay but how it will evolve in a real world patient setting in the medical industry is yet to be defined. 3-D printing technology has the ability to transform the rapid prototyping process and alongside the use of Finite Element Analysis (FEA), produce devices that meet the needs of the end-user and empower the patient.